Does Jeep use non-turnable rotors?? - Off-Road Forums & Discussion Groups
Jeep-Short Wheelbase All discussion of short wheelbase Jeeps: CJ, TJ, YJ and JK

Reply
 
LinkBack Thread Tools Display Modes
post #1 of (permalink) Old 12-24-2002, 08:40 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Does Jeep use non-turnable rotors??

I own a 99 Sahara Wrangler with a 6 Cyl. I have a slight pulsating in the brakes when applied. I had a mechanic check my brakes while he was doing some other work. He told me that I needed new rotors and that the style of rotor I had could not be turned. He said the rotor was a special type that was was stonger than the turnable rotor, and therefore could not be cut. However, he also said that someone (previous owner?) before me had tried to turn it and ruined the rotor. Does anyone know about this type of rotor or is the mechanic trying to take me for all my money. I asked a Jeep service department about the rotor and they said they never heard of that but could not be sure until they looked at the rotor. Does anyone know if there is a special marking on the rotor that designates whether or not it can be turned. Thanks for the help.
Jeff
Sponsored Links
Advertisement
 
post #2 of (permalink) Old 12-24-2002, 09:36 PM
Way Outta Control
 
Join Date: Sep 1999
Location: usa
Posts: 10,815
Thanks: 0
Thanked 1 Time in 1 Post
 
Re: Does Jeep use non-turnable rotors??

They may be out there, but I've yet to see a rotor that
can't be resurfaced - as long as someone hasn't already
destroyed it.
That's a popular thing on Mercedes - to replace rather than
resurface - a scam.
And, a new rotor does not come crooked or need to be surfaced.
It already has the correct surface, and the factory's
multi-million dollar machines get it straighter than
Bubba's $5000 lathe ever will.

The pulsating pedal - caused by runout.
The disc is not the same thickness all the way around, or
when someone tried to refinish it they chucked it in a
lathe wrong.

It should be done "ON THE CAR" - not removed and put in a
separate lathe.
1. The separate lathe mounts it on cones - it cannot mount
accurately, no matter how "good" the technician thinks,
or pretends he is.
Try mounting one, refinish it, take it off, then remount
it on the same lathe again - why is it crooked again?
2. A lathe creates screw marks by the cutter, those make
the pads move when applying the brakes.

What you need is someone with an "ON THE CAR GRINDER."
An honest and competant mechanic.
RRich is offline  
post #3 of (permalink) Old 12-24-2002, 10:40 PM
 
Join Date: Jun 2001
Posts: 1,628
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Does Jeep use non-turnable rotors??

I'd bet he's telling you that because he does not have the correct adapter to mount it on his lathe and would rather sell you a new one than pay someone with the correct tools to turn it.

I ran into the same problem with the rotors on my Suzuki Sidekick. They have a very large center hole (the hub stays on the car when you take the rotor off) and require two of the largest cones to mount it on the lathe. I had 4 or 5 people tell me that they couldn't be turned, I'd have to replace them (for $130 EACH, BTW) and a couple more say they had to be turned on the car. Once I found the guy with two of the big cones for the lathe, turning them wasn't a problem at all [img]images/graemlins/crazy.gif[/img]
dschwab9 is offline  
Sponsored Links
Advertisement
 
post #4 of (permalink) Old 12-24-2002, 11:06 PM
 
Join Date: Apr 2002
Posts: 333
Thanks: 0
Thanked 3 Times in 3 Posts
 
Re: Does Jeep use non-turnable rotors??

As RRich said.....
It can be done, and is best done "on the car".

At my dealership,, we regularly turn rotors on TJ Saharas.
We get it up on the lift, take the wheels off, put the lugnuts back on so the rotor is held in place, then we have a machine that will actually spin the rotor while behaving like a normal brake lathe.

So, no...they aren't "un-turnable" and they can be resurfaced.
Iron_Weasel is offline  
post #5 of (permalink) Old 12-24-2002, 11:41 PM
Way Outta Control
 
Join Date: Sep 1999
Location: usa
Posts: 10,815
Thanks: 0
Thanked 1 Time in 1 Post
 
Re: Does Jeep use non-turnable rotors??

When it's on the car it's mounted on the wheel bearings and
spindles it will stay on. Refinishing it there insures that
it will not have lateral runout caused by cone mounting.
Cone mounting is not repeatable.
Sometimes that's even a problem balancing wheels too,
especially big or heavy ones.

I used to sell an on the car grinder that did a fantastic
job of it. I think Mac Tools still sells it.

Its amazing how many so called "problem cars" I cured with
it. Things like pulsating pedal, squeeling, pulling etc,
and especially ABS systems. Sometimes ABS systems release
the brakes whenever they detect even a small amount of
pulsations caused by the runout. The computer misinterprets
the pulsations as lock-up, and releases the brakes.
That can get really scarey!
RRich is offline  
post #6 of (permalink) Old 12-25-2002, 09:18 AM
Can't Get Enough
 
Join Date: Sep 1999
Location: Cotopaxi, Colorado
Posts: 1,036
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Does Jeep use non-turnable rotors??

Many Jeeps used composite rotors. These rotors are hard to turn without the special composite adapters. They are identified by the "hat", which looks like a thin stamped metal. '99 is a cross over year. The newer rotors are cast, and have a much thicker "hat" area, where it slides onto the hub. Sometimes it is cheaper to replace a hubless rotor than to try to cut it. Most shops call for .5 hours to machine a rotor, and the price of the rotor is about $30. At $60/hr. what would you do?
dorfs is offline  
post #7 of (permalink) Old 12-25-2002, 03:26 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Re: Does Jeep use non-turnable rotors??

The rotors on your Jeep can be turned the mechanic is telling you that because he is scared to turn them. My boss tells people the same thing sometimes. It is hard to turn them because of the fact they are composite rotors with the hub so far offset from the knuckle. just watch out for some people if it sounds wrong it is wrong. None turnable rotors anyhting can be turned with the right adapters.
post #8 of (permalink) Old 12-25-2002, 07:55 PM
I Do This For The Glory
 
JEEPN's Avatar
 
Join Date: Dec 1999
Location: Nobleboro, Maine
Posts: 7,958
Thanks: 0
Thanked 0 Times in 0 Posts
 
Re: Does Jeep use non-turnable rotors??

</font><blockquote><font class="small">In reply to:</font><hr />
Sometimes ABS systems release
the brakes whenever they detect even a small amount of
pulsations caused by the runout. The computer misinterprets
the pulsations as lock-up, and releases the brakes.

[/ QUOTE ]

I would just like to add this is not the problem on the TJ's, they use a tone ring on the axle shaft to regulate the ABS.

Rather than having them turned, check out the prices of them aftermarket, I'll bet it's not that bad.
JEEPN is offline  
post #9 of (permalink) Old 12-25-2002, 10:43 PM
Way Outta Control
 
Join Date: Sep 1999
Location: usa
Posts: 10,815
Thanks: 0
Thanked 1 Time in 1 Post
 
Re: Does Jeep use non-turnable rotors??

Sorry, I wasn't refering to Jeeps in particular when I said
that about pulsations causing release. Sometimes folks
have other vehicles besides Jeeps (why I don't know.)

The pulsations do something to the accumulator valve, which
in turn does whatever it is that does it - I think.

Cadillacs, Chryslers, and a few imported cars have had the
problem that went away when the rotor was made straight.
I had a customer tell me about it - Cadillac - I drove it -
damn near wrecked it for him. He'd been all over town
trying to get someone to get his new brakes to work - to
no avail.
I wasn't sure at the time if it would help, it only had about
.004" runout, not really that much. I think specs called
for .003" max.
I ground it on the car --- what a difference.

Some folks here have shops and may someday find that useful.

Composite rotors are really tricky to use an "off the car"
lathe on, they like to chatter like mad - even with the
adapters it's not easy. By the way, the adapters aren't all
that expensive, around $500 as I remember for the 3 sizes
needed.
RRich is offline  
post #10 of (permalink) Old 12-27-2002, 11:29 PM
**DONOTDELETE**
Guest
 
Posts: n/a
Re: Does Jeep use non-turnable rotors??

They have to turn the rotors when they put on new pads. Find and new brake guy. The pulsing problem is probably caused by warped rotors. The jeep I had 97 2.5 had a special ebrake lamp that only worked about half the time. This resulted in a 10 mile freeway trip with my ebrake engaged, and once they cooled down in noticed the same pulsating in the brake pedal that you are talking about. Especially if it is at low speeds.
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Off-Road Forums & Discussion Groups forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in










Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Posting Rules  
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome